Electromagnet.



II. WIKANDEII.

ELECTROMAGNET.

APPLICATION FILED MAR. 23. I9II.

1 7 1 99,447, Patented Sept. 26, 1916.

2 SHEETS-SHEET I.

III.I

. "lill-S llH/HIII I |NV NTOR xl7/mq W' Mw M ATT'oIINIiY R. WIKANDEH. ELECTROMAGNET. APPLICATION HLED 1.11111. 23. 1911.

PatetedSept. 26, 1.916.

2 SHEETS-SHEET 2.

ATTORNEY RAGNAR WIKANIDER, OF PITTSBURGH, PENNSYLVAIA, ASSIGNGR TO WESTNGHOUSE ELECTBC ANE) MANUFCTURNG COMNY, A CRFORATN OF SYLVANIM ELECTROTIIG-NET.

inesatta.,

Application filed March 23, 191i.

Be it known that I, RAGNAR VIKANDER, a subject of the King of Sweden, and a resident of Pittsburgh, in the county oii Allegheny and State ot" lriennsylvania, have invented ay new and useful improvement in Electromagnets, of which the following is a` specification.

My invention relates to switches for electric circuits and it has special reference to such switches as are electrically operated and are adapted for use in unit switch control systems.

The object et' my invention is to provide a` switch or' the character above indicated that shall be simple and durable in construction, easily adjusted and adapted to provide various operating characteristics and for use under varying conditions of service.

in my cao-pending application, Serial No. 616,479, tiled of even date herewith, l have shown and described a switch operated by an electro-magnet possessing the operating characteristic oit actuating the switch only when energized within predetermined limits. According to my present invention, l provide a switch ha ving,` the same characteristics in gene 1al but possessing a number of irnportant features not onnd elsewhere, as follows:

The adjacent pole pieces oi the stationary and movable core member, which are brought into engagement with each other when the switch is closed, are provided with lianges or enlargements oi' magnetizable material, lwhich materially inlluence the distribution ci? flux in the members when the air gap between them is considerable, but which are spaced slightly from the ends ot the opposed faces so that they do not come into engagement with each other and so that they have no appreciable influence when the switch is closed and the air gap is of least width.

In addition to the foregoing, the core structure comprises an auxiliary core member which is adjustable relative to the main stationary member and is provided with an independent coil which may advantageously be connected in series relation to the electric motor when the switch constitutes a part of a unit switch controller.

Figure l of the accompanying drawings is a side elevation, certain or" the parts beingn broken away and shown in section, cd Fig.

pecication of Letters Patent.

'ai'ented Sept, 2h, time?.

serial no. 616,478.

2 is a front elevation of a switch embodying my invention. Figs. 3, 4f, 5, and G areA detail views ot' the structure ci Figs. l and 2, and Fig. 'T is a` view correspondingto Fig. l of' a. modified switch structure embodyingmy invention.

Referring to the drawings, the switch here shown comprises a supporting rod or bar l having an insulating; jacket 2, a contact post to which stationary Contact member fl is secured. fr stationary lai-shaped core member 5, an auxiliary h-shaped core member G, movable core members 7 and S constituting the armature. oi the magnet and a mo'able contact member i) which coperates with the stationary contact member 4.

rthe stationary members 25 and .3 are rigidly secured to the insulated rod l, the L- shaped niember G is adj astably secured thereto and the niovable' core members T and 8 are pivotally supported upon stationary side brackets l() which are mount-ed thereon.

A maejnetizing coil 1l is mounted upon one arm ot the 'tl-shaped member 5, the other arm 12 oi which is removably secured to side brackets l() by means of screws i3. A. coil ll may be mounted on the outwardly eX- tending a rm ot the i shaped member G, as shown in l and 2. or omitted as shown in Fig. T. The coil l or, it is omitted, the magnetizing coil ll, preierably cnerrized in accordance with the current supplied to the mot in the control oi which the switch is utilized.

The. member f5 is supported by a bracket 'l5 which is bent around the insulated rod or bar l, as shown in Fig. l ot the drawn ings, and adjustment is ei'lfec'ted by means oii a screw it which is screwed into a projec tion l? offf the bracket land is rotatably supported by means of a block 18, said bloclr being clamped to the insulated rod i, directly below the L-shaped member (i, by means of bolts 19 and a clamping member 20. The arm of the core member on which the coil 1l is mounted, is provided, near its outer end, with lateral projections or ianges Q1 of magnetizable material, the outer surfaces of which are substantially parallel to the pole face, but the body oni the core member extends slightly beyond 'the surface oit' the flanges. i

The movable core member 8 is divided into the parts located at the respective sides ci the niorable core member and pivotaliy mcafee? /mounted on a shaft The upper ends of the core member parts 8 are provided with laterally extending inagnetizable projections which are similar to the projections 2l and are correspondingly located but are spaced slightly from the pole laces ol the rrr-embers 8 which come into engagement with the upper arm of the member Strips 2a secured to the inner adjacent surfaces ot the members S and extend downwardly and constitute l.sliaped supports spacing block 2G is pivotally mounted between the members "25 and is provided with a tapped hole 2 to receive a screw-tln'eaded rod 28.

'llhe movable member 7 which, as above indicated, im piroted on the shailt and is located between the members S, extends from the upper arm ot' the member downwardly 'to a point opposite the outwardly extending; arm of the member (l and is provided with side plates 2Q which extend beyond .its upper end and support the movable contact member l). The side plates 29 are also provided with outwardly extending prolin 'tions 3G which pivotally support guide blocks 3l and rlhe rod 28 extends loosely through a hole in the block 31 and is prowided with a collar or enlargenient 311. A. spring' surrounds thel rod and is interposed. between the collar 3l and block Sill.

fr rod 33, which is similar to the rod is pirotally secured, by nwans or a pin El, to contact member l) and extends loosely through a hole 35 in the guide block 32. A. springv 3G surrounds the rod 33 and. tends to produce a rotary movement or the contact member S) about its pivot 37, within limits which are determined by an enlargement 38 on 'the lower end of the rod 33. 'lhe side bracllets l() are secured to the insulated rod l and are electrically connected, by means ol.E bolts l0., to a stud 3) which constitutes one terminal of the switch. Flexible shunts ill complete an electrical connection between the stud 3i) and the contact member 9, since they are fastened to the outer ends el the side brackets l0 and to ledges Ll2 of the contact meml er.

The springF el?) is normally held in compression between the collar ol and the block 3l and has no e lect upon the action of the arn'iature ot' the magnet as a whole but is further compressed by, and opposes a relative movement between, the parts 7 and 8 of the armature as indicated hereinafter. lt is therefore evident that, when both mag; net coils are decnergized, the action of gravity will open the switch and hold the lower end ot' the core member 7 in engagement with the pole 'face o the Lshaped core member 6.

rlhe operation ot' the switch is as follows: lf it is assumed that the switch occupies its open position, the coils ll and llt being denergized and the lower end oli the core member 7 being' in engagement with the pole tace of the l.s`haped core men'iber (3; vthe switch will be closed if the coil ll alone is energized or it' the coil ll. is supplied with a relatively small current. llnder these conditions, the c' re members i' and S will both be attracted by the upper arm oil the core member 5 and will act together. Il the coil ll is omitted and the arm l2 ot the core member 5 is materially less in cross sectirrn than the upper arm as shown in Fig. 7, the switch will be held open provided the coil ll is energized above a predetermined value. since the linx produced in the core member 5 will quickly saturate the arm l2, thereby forcing considerable leakage flux through the L-shaped member (i and the core member i'. llndcr these conditions the core members will not act together, but the core. member T will be held in engagen'ient with the core member (3, while the core member e will be moved into engagement with the upper arm of the core member The position of the core member T, however, letern'rines the position of the switch, since the contact mem- .her S) is carried at its upper end, and the in* depeident movement of the core member 8 will tend only to compress a spring which surrounds the rod QS. ils the current in th(` coil ll is diminished, the leakage lluX passing through the member 7 will bc very rapidly iliminishcd until thc spring Llil will overcome the attraction between the members (l and T and will close the switch.

ll a series ol switches ol the character` above described are so arrangial that their coils ll are successively energized, and il2 the arm l2 olc the core member 5 is substantially equal, in cross section, to the remainder ol the core, substantially the same action may be produced by utilizing' the coil l and makina its current dependent upon the current supplied to a motor or other device controlled by the switches. Under ,these conditions, when the coil lllis euer- `a'ized above a predetermined amount, the core member i' will be held in engagement with the member o and the switch will be held open until the current in the coil l/-l lalls below a predetermined value. The values at which the switch will be closed may be varied by varyingr the number ot turns oll which the coils are composed or by adjusting the air gap at lll between the members 5 and G.

The lateral projections 2l and 23 of the core members 5 and 8 serve to distribute the flux over a wide area when the members are separated by a material air gap, such as that which'exists when the switch is open, since they are nearly llush with the main pole faces of the core members with which they are associated, but, inasmuch as they are separated by an air gap when the main pole faces are in engagement, they have practically no effect on the distribution of flux underV the last named conditions. The projections are particularly valuable for this reason since-they permit a very strong pull, the flux being concentrated in the main pole faces When they are in contact, tending g to hold the members in engagement when the switch is closed, but enable the switch to be more readily held open, either by the action of the coil 14 or bythe leakage flux traversing the core member 6.

My linvention is not restricted to the structural details illustrated, and is only limited by the appended claims. The switch may be utilized for various purposes Within the spirit and scope of 'the invention.

I claimA as my invention:

1. IAn electromagnet comprising a pair ofA core members having an air gap between them, one of said members constituting a shunt magnetic path for the other, an armature member, andmeans for adjusting one of said core members to vary the length of said air gap and to vary the distance betweensaid core member and said armature member.

2. An electro-magnet, comprising a stationary U-shaped core member, a normally stationary, but adjustable, L-shaped core member coperating With said U-shaped core-member, and a movable armature member that is pivotally mounted at the outer end of one of the arms of the U-shaped core member and coperates with both stationary members.

3. An electro-magnet comprising a stationary core member having a flange or enlargement parallel to but slightly spaced from, one of its pole faces, and a coperating movable core member having a corresponding enlargement.

4. An electromagnet comprising relatively movable magnetizable. members between tionary U-shaped core member, a normally stationary, but adjustable, L-shaped core member adjacent to said U-shaped core member and coperating therewith, and a movable armature member that coperates with both stationary members.

(3. An electro-magnet comprising a stationary U-shaped core member, a normally stationary, but adjustable, L-shaped core member coperating with said U-shaped core member, a compound movable core member one part ot' which cooperates with-the stationary members and a second part of which is yieldingly connected to the first part to cooperate only with the U-shaped member.

7. An electromagnet comprising a relatively stationary core member, an auxiliary core member for providing a shunt magnetic path, and a movable member coperating with both core members, said auxiliary -core member being adjustable to vary the reluctance of said shunt magnetic path.

8. Anelectromagnet comprising a pair of relatively movable core members, one of which constitutesa shunt magnetic path for the other, a member coperating with said core members, and means for adjusting one of said core members to simultaneously Vary the distances between it and the other core member and the cooperating member.

ln testimony whereof, I havey hereunto subscribed my name this 21st day of March, 1911. f

RAGNAR WIK ANDER.

lVitnesses: i

STANLEY S'rxioUD, B. B. I'IINEs. 

